I think that after you’ve actually sucked his cock, you can communicate a little more explicitly. I’d avoid leaving a text message history with him mentioning it, but at the beginning of another session and in-person . . . say, while you’re undressing and before you lie down on the table, you can say something like “I really enjoyed my last session with you. I loved getting the chance to suck your cock a little while on the table. Would it be okay for me to suck you more this time and maybe from a more comfortable position? If there’s a limit to how much you’re okay with, that’s okay and I’m asking so I respect your limits.”
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